unless you are using an obsolete compiler, do not use <iostream.h>. it is not part of standatd C++. instead write: #include <iostream> ; and if you want, using namespace std ;

use appropriate variable types. eg. int for integer values

give meaningful names to variables. for example:
int cnt - the number of terms evaluated so far
int max_cnt - the total number of terms to be evaluated
double factorial - factorial of cnt
double term - the term in the series ie. cnt / factorial
double sum - sum of the terms in the series; at the end, it becomes (approximately) the mathematical constant 'e'

you require only one loop, not two.
each time through the loop:
evaluate the new factorial - (previous) factorial * cnt
compute the term - cnt / factorial
add the term to the sum - sum = sum + term
increment cnt